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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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</head>

<body>
    <ul>
        <li>1</li>
        <li>1</li>
        <li>1</li>
        <li>1</li>
        <li class="lili">2</li>
        <li>1</li>
        <li>1</li>
        <li>1</li>
    </ul>
    <script>
        $('ul .lili').nextAll('li').css('color', 'pink') //本身下边的所有同级元素
        $('ul .lili').prevAll('li').css('color', 'red') //本身上边的所有同级元素
    </script>
</body>

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